A Deep Learning Enhanced Novel Software Tool for Laryngeal Dynamics Analysis

Purpose High-speed videoendoscopy (HSV) is an emerging, but barely used, endoscopy technique in the clinic to assess and diagnose voice disorders because of the lack of dedicated software to analyze the data. HSV allows to quantify the vocal fold oscillations by segmenting the glottal area. This challenging task has been tackled by various studies; however, the proposed approaches are mostly limited and not suitable for daily clinical routine. Method We developed a user-friendly software in C# that allows the editing, motion correction, segmentation, and quantitative analysis of HSV data. We further provide pretrained deep neural networks for fully automatic glottis segmentation. Results We freely provide our software Glottis Analysis Tools (GAT). Using GAT, we provide a general threshold-based region growing platform that enables the user to analyze data from various sources, such as in vivo recordings, ex vivo recordings, and high-speed footage of artificial vocal folds. Additionally, especially for in vivo recordings, we provide three robust neural networks at various speed and quality settings to allow a fully automatic glottis segmentation needed for application by untrained personnel. GAT further evaluates video and audio data in parallel and is able to extract various features from the video data, among others the glottal area waveform, that is, the changing glottal area over time. In total, GAT provides 79 unique quantitative analysis parameters for video- and audio-based signals. Many of these parameters have already been shown to reflect voice disorders, highlighting the clinical importance and usefulness of the GAT software. Conclusion GAT is a unique tool to process HSV and audio data to determine quantitative, clinically relevant parameters for research, diagnosis, and treatment of laryngeal disorders. Supplemental Material https://doi.org/10.23641/asha.14575533.

Computational simulations of respiratory-laryngeal interactions and their effects on lung volume termination during phonation: Considerations for hyperfunctional voice disorders

Glottal resistance plays an important role in airflow conservation, especially in the context of high vocal demands. However, it remains unclear if laryngeal strategies most effective in controlling airflow during phonation are consistent with clinical manifestations of vocal hyperfunction. This study used a previously validated three-dimensional computational model of the vocal folds coupled with a respiratory model to investigate which laryngeal strategies were the best predictors of lung volume termination (LVT) and how these strategies' effects were modulated by respiratory parameters. Results indicated that the initial glottal angle and vertical thickness of the vocal folds were the best predictors of LVT regardless of subglottal pressure, lung volume initiation, and breath group duration. The effect of vertical thickness on LVT increased with the subglottal pressure-highlighting the importance of monitoring loudness during voice therapy to avoid laryngeal compensation-and decreased with increasing vocal fold stiffness. A positive initial glottal angle required an increase in vertical thickness to complete a target utterance, especially when the respiratory system was taxed. Overall, findings support the hypothesis that laryngeal strategies consistent with hyperfunctional voice disorders are effective in increasing LVT, and that conservation of airflow and respiratory effort may represent underlying mechanisms in those disorders.

Semi-occluded vocal tract exercises in healthy young adults: Articulatory, acoustic, and aerodynamic measurements during phonation at threshold

Semi-occluded vocal tract exercises (SOVTEs) are increasingly popular as therapeutic exercises for patients with voice disorders. This popularity is reflected in the growing research literature, investigating the scientific principles underlying SOVTEs and their practical efficacy. This study examines several acoustic, articulatory, and aerodynamic variables before, during, and after short-duration (15 s) SOVTEs with a narrow tube in air. Participants were 20 healthy young adults, and all variables were measured at threshold phonation levels. Acoustic variables were measured with a microphone and a neck accelerometer, and include fundamental frequency, glottal open quotient, and vocal efficiency. Articulatory variables were measured with ultrasound, and include measures of the tongue tip, tongue dorsum, and posterior tongue height, and horizontal tongue length. Aerodynamic variables were measured with an intraoral pressure transducer and include subglottal, intraoral, and transglottal pressures. Lowering of the posterior tongue height and tongue dorsum height were observed with gender-specific small changes in the fundamental frequency, but there were no significant effects on the transglottal pressure or vocal efficiency. These findings suggest that the voices of healthy young adults already approach optimal performance, and the continued search for scientific evidence supporting SOVTEs should focus on populations with voice disorders.

Comparison of Glidescope Core, C-MAC Miller and conventional Miller laryngoscope for difficult airway management by anesthetists with limited and extensive experience in a simulated Pierre Robin sequence: A randomized crossover manikin study

BACKGROUND

Video laryngoscopy is an effective tool in the management of difficult pediatric airway. However, evidence to guide the choice of the most appropriate video laryngoscope (VL) for airway management in pediatric patients with Pierre Robin syndrome (PRS) is insufficient. Therefore, the aim of this study was to compare the efficacy of the Glidescope® Core™ with a hyperangulated blade, the C-MAC® with a nonangulated Miller blade (C-MAC® Miller) and a conventional Miller laryngoscope when used by anesthetists with limited and extensive experience in simulated Pierre Robin sequence.

METHODS

Forty-three anesthetists with limited experience and forty-three anesthetists with extensive experience participated in our randomized crossover manikin trial. Each performed endotracheal intubation with the Glidescope® Core™ with a hyperangulated blade, the C-MAC® with a Miller blade and the conventional Miller laryngoscope. "Time to intubate" was the primary endpoint. Secondary endpoints were "time to vocal cords", "time to ventilate", overall success rate, number of intubation attempts and optimization maneuvers, Cormack-Lehane score, severity of dental trauma and subjective impressions.

RESULTS

Both hyperangulated and nonangulated VLs provided superior intubation conditions. The Glidescope® Core™ enabled the best glottic view, caused the least dental trauma and significantly decreased the "time to vocal cords". However, the failure rate of intubation was 14% with the Glidescope® Core™, 4.7% with the Miller laryngoscope and only 2.3% with the C-MAC® Miller when used by anesthetists with extensive previous experience. In addition, the "time to intubate", the "time to ventilate" and the number of optimization maneuvers were significantly increased using the Glidescope® Core™. In the hands of anesthetists with limited previous experience, the failure rate was 11.6% with the Glidescope® Core™ and 7% with the Miller laryngoscope. Using the C-MAC® Miller, the overall success rate increased to 100%. No differences in the "time to intubate" or "time to ventilate" were observed.

CONCLUSIONS

The nonangulated C-MAC® Miller facilitated correct placement of the endotracheal tube and showed the highest overall success rate. Our results therefore suggest that the C-MAC® Miller could be beneficial and may contribute to increased safety in the airway management of infants with PRS when used by anesthetists with limited and extensive experience.

Fluid-structure-acoustic interactions in an ex vivo porcine phonation model

In the clinic, many diagnostic and therapeutic procedures focus on the oscillation patterns of the vocal folds (VF). Dynamic characteristics of the VFs, such as symmetry, periodicity, and full glottal closure, are considered essential features for healthy phonation. However, the relevance of these individual factors in the complex interaction between the airflow, laryngeal structures, and the resulting acoustics has not yet been quantified. Sustained phonation was induced in nine excised porcine larynges without vocal tract (supraglottal structures had been removed above the ventricular folds). The multimodal setup was designed to simultaneously control and monitor key aspects of phonation in the three essential parts of the larynx. More specifically, measurements will comprise (1) the subglottal pressure signal, (2) high-speed recordings in the glottal plane, and (3) the acoustic signal in the supraglottal region. The automated setup regulates glottal airflow, asymmetric arytenoid adduction, and the pre-phonatory glottal gap. Statistical analysis revealed a beneficial influence of VF periodicity and glottal closure on the signal quality of the subglottal pressure and the supraglottal acoustics, whereas VF symmetry only had a negligible influence. Strong correlations were found between the subglottal and supraglottal signal quality, with significant improvement of the acoustic quality for high levels of periodicity and glottal closure.

A one-dimensional flow model enhanced by machine learning for simulation of vocal fold vibration

A one-dimensional (1D) unsteady and viscous flow model that is derived from the momentum and mass conservation equations is described, and to enhance this physics-based model, a machine learning approach is used to determine the unknown modeling parameters. Specifically, an idealized larynx model is constructed and ten cases of three-dimensional (3D) fluid-structure interaction (FSI) simulations are performed. The flow data are then extracted to train the 1D flow model using a sparse identification approach for nonlinear dynamical systems. As a result of training, we obtain the analytical expressions for the entrance effect and pressure loss in the glottis, which are then incorporated in the flow model to conveniently handle different glottal shapes due to vocal fold vibration. We apply the enhanced 1D flow model in the FSI simulation of both idealized vocal fold geometries and subject-specific anatomical geometries reconstructed from the magnetic resonance imaging images of rabbits' larynges. The 1D flow model is evaluated in both of these setups and shown to have robust performance. Therefore, it provides a fast simulation tool that is superior to the previous 1D models.

Glottal Aerodynamics Estimated From Neck-Surface Vibration in Women With Phonotraumatic and Nonphonotraumatic Vocal Hyperfunction

Purpose The purpose of this study was to determine whether estimates of glottal aerodynamic measures based on neck-surface vibration are comparable to those previously obtained using oral airflow and air pressure signals (Espinoza et al., 2017) in terms of discriminating patients with phonotraumatic and nonphonotraumatic vocal hyperfunction (PVH and NPVH) from vocally healthy controls. Method Consecutive /pae/ syllables at comfortable and loud level were produced by 16 women with PVH (organic vocal fold lesions), 16 women with NPVH (primary muscle tension dysphonia), and 32 vocally healthy women who were each matched to a patient according to age and occupation. Subglottal impedance-based inverse filtering of the anterior neck-surface accelerometer (ACC) signal yielded estimates of peak-to-peak glottal airflow, open quotient, and maximum flow declination rate. Average subglottal pressure and microphone-based sound pressure level (SPL) were also estimated from the ACC signal using subject-specific linear regression models. The ACC-based measures of glottal aerodynamics were normalized for SPL and statistically compared between each patient and matched-control group. Results Patients with PVH and NPVH exhibited lower SPL-normalized glottal aerodynamics values than their respective control subjects (p values ranging from < .01 to .07) with very large effect sizes (1.04-2.16), regardless of loudness condition or measurement method (i.e., ACC-based values maintained discriminatory power). Conclusions The results of this study demonstrate that ACC-based estimates of most glottal aerodynamic measures are comparable to those previously obtained from oral airflow and air pressure (Espinoza et al., 2017) in terms of differentiating between hyperfunctional (PVH and NPVH) and normal vocal function. ACC-based estimates of glottal aerodynamic measures may be used to assess vocal function during continuous speech and enables this assessment of daily voice use during ambulatory monitoring to provide better insight into the pathophysiological mechanisms associated with vocal hyperfunction.

Laryngeal tubes and laryngeal mask devices for supraglottic airway management in out-of-hospital emergency care: a systematic review

Various supraglottic devices are currently available for airway management and are used widely in emergency situations because they are easy to position. We undertook a systematic review of the literature comparing laryngeal tubes and various laryngeal mask airway devices (LMAs) to determine which ones can be used most efficiently in emergencies. Nine databases were searched, as follows: Cochrane Library Plus, MEDLINE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Dialnet, Global Health, Nursing & Allied Health Database, CUIDEN, the Web of Science, and ScienceDirect. We collected studies published between 2014 and 2019 in Spanish, English, French, and Portuguese that compared laryngeal tubes to LMAs of different types for supraglottic airway management. Eighteen studies were selected for analysis after critical reading. Significant differences were not seen between tubes and LMAs with respect to most variables, but in certain contexts the oropharyngeal seal and speed of insertion were superior with laryngeal tubes; however, when fiberoptic bronchoscopes were then inserted the view of the glottis was poor. The different contexts in which these devices are used and the scarcity of studies comparing laryngeal tubes to LMAs does not allow us to identify clear differences among them with respect to efficiency. However, tubes seem to offer poorer visibility of the glottis according to evaluation with fiberoptic scopes, a factor to bear in mind if tracheal intubation, which is considered the gold standard, might become necessary.

Indicators of anterior-posterior phase difference in glottal opening measured from natural production of vowels

Voiced speech is generated by the glottal flow interacting with vocal fold vibrations. However, the details of vibrations in the anterior-posterior direction (the so-called zipper-effect) and their correspondence with speech and other glottal signals are not fully understood due to challenges in direct measurements of vocal fold vibrations. In this proof-of-concept study, the potential of four parameters extracted from high-speed videoendoscopy (HSV), electroglottography, and speech signals to indicate the presence of a zipper-type glottal opening is investigated. Comparison with manual labeling of the HSV videos highlighted the importance of multiple parameter-signal pairs in indicating the presence of a zipper-type glottal opening.

Laryngeal strategies to minimize vocal fold contact pressure and their effect on voice production

The goal of this study is to identify laryngeal strategies that minimize vocal fold contact pressure while producing a target sound pressure level (SPL) using a three-dimensional voice production model. The results show that while the subglottal pressure and transverse stiffness can be manipulated to reduce the peak contact pressure, such manipulations also reduce the SPL, and are thus less effective in reducing contact pressure in voice tasks targeting a specific SPL level. In contrast, changes in the initial glottal angle and vocal fold vertical thickness that reduce the contact pressure also increase the SPL. Thus, in voice tasks targeting a specific SPL, such changes in the initial glottal angle and vertical thickness also lower the subglottal pressure, which further reduces the peak contact pressure. Overall the results show that for voice tasks with a target SPL level, vocal fold contact pressure can be significantly reduced by adopting a barely abducted glottal configuration or reducing the vocal fold vertical thickness. Aerodynamic measures are effective in identifying voice production with large initial glottal angles, but by themselves alone are not useful in differentiating hyperadducted vocal folds from barely abducted vocal folds, which may be better differentiated by closed quotient and voice type measures.

Changes in the voice production of solo singers across concert halls

To investigate the influence of room acoustics on singing, four lyrical singers (soprano, mezzo-soprano, tenor, baritone) performed four musical pieces in eight different venues (from dry studio to reverberant church). In addition to vocal intensity measured by a near-field microphone, glottal behavior (vibratory fundamental frequency and contact quotient) was assessed by electroglottography. Statistical linear mixed models showed that the variance in vocal performance was partly explained by room acoustics. Complementary to previous results on voice musical features influenced by timbre and level of the room's response, voice production parameters were mostly influenced by spatial aspects of the room's response.

Analysis of the tonal sound generation during phonation with and without glottis closure

The human phonation is characterized by periodical oscillations of the vocal folds with a complete glottis closure. In contrast, a glottal insufficiency (GI) represents an oscillation without glottis closure resulting in a breathy and weak voice. In this study, flow-induced oscillations of silicone vocal folds were modeled with and without glottis closure. The measurements comprised the flow pressure in the model, the generated sound, and the high-speed footage of the vocal fold motion. The analysis revealed that the sound signal for vocal fold oscillations without closure exhibits a lower number of harmonic tones with smaller amplitudes compared to the case with complete closure. The time series of the pressure signals showed small and periodical oscillations occurring less frequently and with smaller amplitude for the GI case. Accordingly, the pressure spectra include fewer harmonics similar to the sound. The analysis of the high-speed videos indicates that the strength of the pressure oscillations correlates with the divergence angle of the glottal duct during the closing motion. Physiologically, large divergence angles typically occur for a pronounced mucosal wave motion with glottis closure. Thus, the results indicate a correlation between the intensity of the mucosal wave and the development of harmonic tones.

Bayesian estimation of vocal function measures using laryngeal high-speed videoendoscopy and glottal airflow estimates: An in vivo case study

This study introduces the in vivo application of a Bayesian framework to estimate subglottal pressure, laryngeal muscle activation, and vocal fold contact pressure from calibrated transnasal high-speed videoendoscopy and oral airflow data. A subject-specific, lumped-element vocal fold model is estimated using an extended Kalman filter and two observation models involving glottal area and glottal airflow. Model-based inferences using data from a vocally healthy male individual are compared with empirical estimates of subglottal pressure and reference values for muscle activation and contact pressure in the literature, thus providing baseline error metrics for future clinical investigations.

Surgical Considerations for an Awake Tracheotomy During the COVID-19 Pandemic

Background: The current global COVID-19 pandemic is caused by the novel coronavirus Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2). Given that SARS-CoV-2 is highly transmissible, surgical societies have recommended that procedures with a high risk of aerosolization be avoided or delayed. However, some high-risk procedures, such as those related to head and neck malignancies, cannot always be delayed. Care must be taken during aerosol-generating procedures to minimize viral transmission as much as possible. Preoperative testing for COVID-19, limited operating room personnel, adequate personal protective equipment, and surgical technique are factors to consider for high-risk procedures. Methods: This article presents the case of an awake tracheotomy performed for a transglottic mass causing airway obstruction. Results: With detailed planning and specific techniques, the amount of aerosolization was reduced, and the procedure was performed as safely as possible. Conclusion: This case provides a template for future aerosol-generating procedures during respiratory pandemics.

Phonation threshold pressure using a 3-mass model of phonation with empirical pressure values

Understanding the control parameters that influence phonation threshold pressure can have important implications for ease of phonation. Using a computer model of phonation can aid in studying parameters not easily controllable through human experimental work and may provide a means of explaining variations seen across human participants. A vertical 3-mass computer model of phonation with empirical driving pressures was used to obtain phonation threshold pressures for a variety of prephonatory conditions that may be realistically produced by humans. The resulting phonation threshold pressures are reasonable compared to results from human studies and may extend beyond the range of phonatory control parameters studied in human experiments. In addition, the present work adds a formula for calculating phonation threshold pressure based on the prephonatory glottal angle, the tension of the vocal folds, and the prephonatory diameter. Of special interest is that, as the prephonatory angle of convergence increases from 0 degrees (the rectangular glottis condition), the phonation threshold pressure increases in a nearly linear fashion.

[Preliminary study of medialization thyroplasty for unilateral vocal fold immobility]

Objective:To explore the feasibility and effectiveness of medialization thyroplasty for the treatment of unilateral vocal fold immobility （UVFI）. Method:Eight UVFI patients were performed medialization thyroplasty under local anesthesia. We made a window in the thyroid cartilage under local anesthesia, then insert the preformed silicone implant. The paralyzed vocal fold was medialized to make the glottis closed. Fibrolaryngoscope video recording, subjective voice analysis and CT thin slice scan of larynx were done before and after surgery to evaluate closure of vocal cords, improvement of voice and position of implantation. Result:The preoperative and postoperative voice handicap index 30（VHI-30） of the 8 patients were 91.5（64.5, 97.5） and 22.5（5.0, 47.5） respectively, which showed statistical difference（P<0.05）. GRBAS results: The postoperative G, R, B, A were all smaller than preoperative ones, which showed statistical difference（P<0.05）; the pre and postoperative S was both 0. The fibrolaryhgoscope recording showed the preoperative and postoperative score of incomplete glottis closure was 1.0（1.0, 1.0） and 4.0（2.5, 5.0） respectively, which showed statistical difference（P<0.05）. Postoperative laryngeal CT showed significant vocal cord medialization on the affected side. Aspiration was significantly improved in 4 patients who were suffered from this symptom before the surgery. No complication occurred with the 8 patients during 5 to 48 months follow up. Conclusion:Medialization thyroplasty can effectively improve vocalization and quality of life in patients with UVFI.

Outcomes of carotid-sparing IMRT for T1 glottic cancer: Comparison with conventional radiation

OBJECTIVES

We aim to report oncologic outcomes after conventional radiotherapy (ConRT) using opposed lateral beams and intensity-modulated radiation therapy (IMRT) for tumor (T)1 nodal (N)0 T1 N0 glottic squamous cell carcinoma.

STUDY DESIGN

Retrospective case-control study.

METHODS

We retrospectively reviewed demographic, disease, and treatment characteristics for patients treated at our institution during 2000 to 2013.

RESULTS

One hundred fifty-three patients (71%) were treated using ConRT and 62 (29%) using IMRT. The median follow-up for all patients was 68 months. There was no statistically significant difference in 5-year local control between patients with T1a versus T1b disease (94% vs. 89%, respectively, P = 0.5). Three-year locoregional control for patients treated with ConRT was 94% compared to 97% with IMRT (P = 0.4). Three-year overall survival (OS) for patients treated with ConRT was 92.5% compared with 100% with IMRT (P = 0.1). Twelve of 14 patients with local recurrence underwent salvage surgery with 5-year ultimate locoregional control of 98.5% and 97.1% in the ConRT and IMRT cohorts, respectively (P = 0.7). Multivariate analysis showed age < 60 years (P < 0.0001) and pretreatment Eastern Cooperative Oncology Group performance status <2 (P = 0.0022) to be independent correlates of improved OS. Postradiation cerebrovascular events were in four patients in the ConRT cohort (3%), whereas no patients in the IMRT cohort suffered any events.

CONCLUSION

Because the oncologic outcomes for patients treated with IMRT were excellent and IMRT allows for carotid sparing, we have transitioned to IMRT as our standard for most patients with T1 glottic cancer.

LEVEL OF EVIDENCE

3b Laryngoscope, 130:146-153, 2020.

Experimental and Computational Modeling of the Effects of Voice Therapy Using Tubes

Purpose Phonations into a tube with the distal end either in the air or submerged in water are used for voice therapy. This study explores the effective mechanisms of these therapy methods. Method The study applied a physical model complemented by calculations from a computational model, and the results were compared to those that have been reported for humans. The effects of tube phonation on vocal tract resonances and oral pressure variation were studied. The relationships of transglottic pressure variation in time P_trans ( t) versus glottal area variation in time GA( t) were constructed. Results The physical model revealed that, for the phonation on [u:] vowel through a glass resonance tube ending in the air, the 1st formant frequency ( F₁ ) decreased by 67%, from 315 Hz to 105 Hz, thus slightly above the fundamental frequency ( F₀ ) that was set to 90-94 Hz . For phonation through the tube into water, F₁ decreased by 91%-92%, reaching 26-28 Hz, and the water bubbling frequency F_b ≅ 19-24 Hz was just below F₁ . The relationships of P_trans ( t) versus GA( t) clearly differentiate vowel phonation from both therapy methods, and show a physical background for voice therapy with tubes. It is shown that comparable results have been measured in humans during tube therapy. For the tube in air, F₁ descends closer to F₀ , whereas for the tube in water, the frequency F_b occurs close to the acoustic-mechanical resonance of the human vocal tract. Conclusion In both therapy methods, part of the airflow energy required for phonation is substituted by the acoustic energy utilizing the 1st acoustic resonance. Thus, less flow energy is needed for vocal fold vibration, which results in improved vocal efficiency. The effect can be stronger in water resistance therapy if the frequency F_b approaches the acoustic-mechanical resonance of the vocal tract, while simultaneously F₀ is voluntarily changed close to F_1.

Effect of Dynamic Versus Stylet-Guided Intubation on First-Attempt Success in Difficult Airways Undergoing Glidescope Laryngoscopy: A Randomized Controlled Trial

BACKGROUND

Tracheal intubation failure in patients with difficult airway is still not uncommon. While videolaryngoscopes such as the Glidescope offer better glottic vision due to an acute-angled blade, this advantage does not always lead to an increased success rate because successful insertion of the tube through the vocal cords may be the limiting factor. We hypothesize that combined use of Glidescope and fiberscope used only as a dynamic guide facilitates tracheal intubation compared to a conventional Glidescope technique with a preshaped nondynamic stylet.

METHODS

One hundred sixty adult patients with predicted difficult airway were randomly assigned to a conventional Glidescope (standard Glidescope group) or a combined Glidescope + fiberscope group intubation. In the Glidescope + fiberscope group under direct vision from the Glidescope, tracheal intubation was performed using the fiberscope as a guide without using fiberoptic vision, while in the standard Glidescope group, a conventional stylet-guided intubation technique was performed. We evaluated the rate of tracheal intubation success at first attempt as the primary end point (Fisher exact test). The difference between groups in airway injury, time to successful intubation, and the need for an alternative technique was also evaluated.

RESULTS

First-attempt intubation success was higher in the Glidescope + fiberscope group than in the standard Glidescope group (91% vs 67%; P = .0012; fragility index, 8; absolute risk reduction, 24% [95% CI, 12%-36%]). Median time to successful tracheal intubation was shorter in the Glidescope + fiberscope group (50 vs 64 seconds; P = .035). Airway injury rate was lower in the Glidescope + fiberscope group than in the standard Glidescope group (1% vs 11%; P = .035; fragility index, 1; absolute risk reduction, 10% [95% CI, 3%-18%]). Alternative rescue technique requirements to achieve tracheal intubation were higher in the standard Glidescope group (24% vs 4%; P < .001; fragility index, 7).

CONCLUSIONS

The use of a dynamic, flexible guide during a Glidescope laryngoscopy in patients with a predicted difficult airway compared to a standard intubation technique improves first-attempt intubation success, decreases the incidence of airway injury and time to successful intubation, as well as the need of an alternative technique to succeed.

Office-based retrograde transtracheal application of mitomycin C

OBJECTIVES

The utility of topical mitomycin C (MMC) as an adjuvant treatment in the management of laryngeal and tracheal stenosis has been studied; however, the ideal timing of MMC application has not been fully elucidated. There is a paucity of studies evaluating the timing of MMC application after surgical airway intervention for stenosis. The purpose of this study is to describe a novel technique for MMC application that allows for delayed application in the unsedated, office-based setting, approximately one week following endoscopic airway dilation.

METHODS

A technique for retrograde transtracheal application of MMC was developed and utilized in 3 tracheostomy-dependent patients with subglottic stenosis and glottic stenosis with bilateral vocal fold immobility. After administration of topical anesthesia, a MMC (0.4 mg/ml) coated pledget was advanced via a transtracheal approach and directed to the area of stenosis in retrograde fashion using endoscopic frontal sinus instruments. Appropriate positioning of the pledget was confirmed via transnasal flexible fiberoptic laryngoscopy.

RESULTS

All 3 patients underwent successful in-office retrograde application of MMC onto the area of laryngeal stenosis 7-9 days after their preceding surgery. There were no complications. Two patients achieved decannulation while the third patient's management was interrupted due to cancer treatment.

CONCLUSIONS

We present a novel and well tolerated technique for delayed in-office application of MMC in tracheostomy-dependent patients with laryngeal stenosis. This approach can facilitate the study of the ideal timing of topical MMC use in airway stenosis.

Effect of a Strategy of a Supraglottic Airway Device vs Tracheal Intubation During Out-of-Hospital Cardiac Arrest on Functional Outcome: The AIRWAYS-2 Randomized Clinical Trial

IMPORTANCE

The optimal approach to airway management during out-of-hospital cardiac arrest is unknown.

OBJECTIVE

To determine whether a supraglottic airway device (SGA) is superior to tracheal intubation (TI) as the initial advanced airway management strategy in adults with nontraumatic out-of-hospital cardiac arrest.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, cluster randomized clinical trial of paramedics from 4 ambulance services in England responding to emergencies for approximately 21 million people. Patients aged 18 years or older who had a nontraumatic out-of-hospital cardiac arrest and were treated by a participating paramedic were enrolled automatically under a waiver of consent between June 2015 and August 2017; follow-up ended in February 2018.

INTERVENTIONS

Paramedics were randomized 1:1 to use TI (764 paramedics) or SGA (759 paramedics) as their initial advanced airway management strategy.

MAIN OUTCOMES AND MEASURES

The primary outcome was modified Rankin Scale score at hospital discharge or 30 days after out-of-hospital cardiac arrest, whichever occurred sooner. Modified Rankin Scale score was divided into 2 ranges: 0-3 (good outcome) or 4-6 (poor outcome; 6 = death). Secondary outcomes included ventilation success, regurgitation, and aspiration.

RESULTS

A total of 9296 patients (4886 in the SGA group and 4410 in the TI group) were enrolled (median age, 73 years; 3373 were women [36.3%]), and the modified Rankin Scale score was known for 9289 patients. In the SGA group, 311 of 4882 patients (6.4%) had a good outcome (modified Rankin Scale score range, 0-3) vs 300 of 4407 patients (6.8%) in the TI group (adjusted risk difference [RD], -0.6% [95% CI, -1.6% to 0.4%]). Initial ventilation was successful in 4255 of 4868 patients (87.4%) in the SGA group compared with 3473 of 4397 patients (79.0%) in the TI group (adjusted RD, 8.3% [95% CI, 6.3% to 10.2%]). However, patients randomized to receive TI were less likely to receive advanced airway management (3419 of 4404 patients [77.6%] vs 4161 of 4883 patients [85.2%] in the SGA group). Two of the secondary outcomes (regurgitation and aspiration) were not significantly different between groups (regurgitation: 1268 of 4865 patients [26.1%] in the SGA group vs 1072 of 4372 patients [24.5%] in the TI group; adjusted RD, 1.4% [95% CI, -0.6% to 3.4%]; aspiration: 729 of 4824 patients [15.1%] vs 647 of 4337 patients [14.9%], respectively; adjusted RD, 0.1% [95% CI, -1.5% to 1.8%]).

CONCLUSIONS AND RELEVANCE

Among patients with out-of-hospital cardiac arrest, randomization to a strategy of advanced airway management with a supraglottic airway device compared with tracheal intubation did not result in a favorable functional outcome at 30 days.

TRIAL REGISTRATION

ISRCTN Identifier: 08256118.

[EVALUATION OF THE EFFICACY OF THE EXTENDED-COMBINED OPERATIONS ON THE ZONES OF PRE- AND PARATRACHEAL METASTASIS IN SUBGLOTTIC CANCER OF THE LARYNX]

After a retrospective study of the history of patients with a diagnosis of laryngeal cancer (2151 people), as well as the analysis of their own clinical materials, subglottic cancer was found in 103 patients, which was 4.8% of the total number of patients admitted to the hospital. One group of patients (n=39) underwent laryngectomy with subsequent irradiation, another group (n=64) was carried out by us developed and introduced into practice the method of the extended-combined laryngectomy. This method involves the mobilization and excision of the cervical tissue with lymph nodes located within it at the level VI level, the mobilization of the larynx and its removal at the level of the V-th or VI-th tracheal rings, as well as the dissection or thyroid share from the side of lesion in the unilateral localization, or complete dissection in the circular localization of the tumor. The comparative analysis was carried out on the frequency of metastasis in the pre- and paratracheal zones during the subglottic cancer of the larynx. A statistically significant (p<0.001) decrease in the incidence of metastases was observed in the advanced-combined laryngectomy (14.5%) compared with the traditional treatment (66.5%). If we consider that the main cause of death of patients with a tumor, both in subglottic cancer of the larynx and any other localization is metastasis, the development and introduction of new surgical methods that reduce the incidence of metastasis is a major breakthrough in practical oncology.

Radiotherapy for T1 Carcinoma of the Glottis

Aims and background

The management of patients with T1 carcinoma of the glottic larynx is controversial, because surgery and radiation therapy are reported to be effective treatments. Several studies have shown radiotherapy to be safe and effective, with a high percentage of voice preservation and minimal complications, but most Italian physicians prefer to surgically treat such patients.

Methods

From 1980 to 1990, 36 patients with stage I squamous cell glottic carcinoma were treated with radiotherapy alone at the Institute of Radiology of University of Rome “La Sapienza”. In all patients the irradiation fields were limited to the larynx, with field size ranging from 4 × 4 cm to 7 × 7 cm. Total tumor doses ranged between 51 and 70 Gy (median 60 Gy) with a mean number of 30 fractions of 2 to 3 Gy per fraction (3 or 5 fractions per week).

Results

After a median follow-up of 98 months, we observed an overall survival rate at 5 years of 91.4% and actuarial 10-year survival of 85.7%. Local control was achieved in 97.1% of cases, with an event-free survival of 94.2% at 5 and 10 years. No major complications like necrosis or persistent edema of the larynx were observed. Minor complications like dysphonia (8%) and dysphagia (5.5%) were temporary; laryngeal function was completely preserved at the end of therapy. Final voice quality ranged from good to excellent.

Conclusions

Our series confirms that radiation therapy has a major role in the management of early glottic cancer, with results comparable to surgical approaches and with better voice preservation.